A method of providing stereoscopic display by using two images having parallax has conventionally been known. For example, a technique for artificially causing stereoscopic effect by providing parallax images (left and right images) obtained from two cameras to left and right eyes respectively is known.
A typical method of generating a parallax image includes a method of arranging an object to be displayed in a three-dimensional virtual space and picking up an image of this object with a pair of virtual cameras. In a case where such a method is adopted, when the pair of virtual cameras is relatively close to an object, the object looks like popping up toward the front from a display surface when viewed from a user (observer). Namely, parallax of the object at the display surface becomes relatively great and consequently the user visually recognizes the object with higher stereoscopic effect.
An exemplary embodiment provides a recording medium storing a display control program, a display system, a display control method, and a display capable of realizing more natural stereoscopic display.
According to an exemplary embodiment, a recording medium storing a display control program for controlling a display capable of providing stereoscopic display is provided. The display control program includes image output instructions for outputting an image for left eye and an image for right eye to the display, parallax calculation instructions for calculating parallax produced when an object is displayed on the display, and movement-and-display instructions for carrying out at least one of movement of a displayed object out of an effective display range and movement of a not-displayed object into the effective display range in accordance with the calculated parallax.
According to the exemplary embodiment, each object is stereoscopically displayed with parallax that should originally be produced. An object of which parallax produced when the object is displayed on the display satisfies a prescribed condition is switched from a display state to a non-display state or switched from a non-display state to a display state. Therefore, stereoscopic effect between the stereoscopically displayed objects can naturally be expressed.
According to am exemplary embodiment, the movement-and-display instructions cause, in response to parallax produced in the displayed object satisfying a first condition, movement of the object out of the effective display range, and cause, in response to parallax produced when the not-displayed object is displayed on the display satisfying a second condition different from the first condition, movement of the object into the effective display range.
According to the exemplary embodiment, since a condition involved with display/non-display of an object is different, in a case where produced parallax satisfies a condition for display, even an object once switched to non-display is switched again to a display state. Therefore, smoother stereoscopic display can also be realized.
According to an exemplary embodiment, the movement-and-display instructions include image generation instructions for generating the image for left eye and the image for right eye by picking up images of an object arranged in a virtual space with a pair of virtual cameras and positional relation updating instructions for updating relative positional relation between the object arranged in the virtual space and the pair of virtual cameras.
According to the exemplary embodiment, control of parallax produced when an object is displayed on the display can be realized by adjusting relative positional relation between the object in the virtual space and the pair of virtual cameras. Therefore, processing can be simplified even when a plurality of objects are stereoscopically displayed.
According to an exemplary embodiment, the movement-and-display instructions cause movement of the displayed object out of the effective display range or movement of the not-displayed object into the effective display range based on comparison of a distance from a reference plane which is a plane including the pair of virtual cameras in the virtual space to the object with a prescribed value.
According to an exemplary embodiment, the movement-and-display instructions cause movement of the displayed object out of the effective display range when a distance from the reference plane to the object is equal to or smaller than a first prescribed value and cause movement of the not-displayed object into the effective display range when a distance from the reference plane to the object is equal to or greater than a second prescribed value different from the first prescribed value.
According to an exemplary embodiment, the second prescribed value is greater than the first prescribed value.
According to the exemplary embodiment, such a situation that processing for moving a displayed object out of the effective display range to set the object to a not-displayed state and processing for setting a not-displayed object to a displayed state and then moving the object to a position of display of the object are repeatedly performed can be prevented.
According to an exemplary embodiment, the movement-and-display instructions cause movement of the object such that parallax produced in the moving object is substantially maintained.
According to the exemplary embodiment, natural stereoscopic display also of a moving object can be provided.
According to an exemplary embodiment, the positional relation updating instructions provide display of the object as moving, by moving the object in an orientation in parallel to the reference plane within the virtual space.
According to the exemplary embodiment, by moving the object in an orientation in parallel to the reference plane within the virtual space, parallax produced in the moving object can substantially be maintained. Therefore, it is not necessary to sequentially calculate parallax produced in the moving object and processing can be simplified.
According to an exemplary embodiment, the movement-and-display instructions cause gradual movement of the object.
According to the exemplary embodiment, the object can be moved out of the effective display range, taking a certain period of time. Therefore, such an effect that the object is not immediately set to non-display but it is set to non-display some time later can be provided.
According to an exemplary embodiment, the movement-and-display instructions differ an orientation of movement of the object in accordance with a position of display of the object on a display surface of the display.
According to the exemplary embodiment, since a direction of movement of the object out of the effective display range and/or a direction of movement of the object from the outside of the effective display range can be determined based on a position of display of the object, a direction of movement in switching between a display state and a non-display state of the object can more appropriately be set.
According to an exemplary embodiment, the movement-and-display instructions differ an orientation of movement of the object in accordance with a distance from a position of display of the object to outside of the effective display range.
According to the exemplary embodiment, since a direction of movement of the object out of the effective display range and/or a direction of movement of the object from the outside of the effective display range can be determined based on a distance from a position of display to the outside of the effective display range, a direction of movement in switching between a display state and a non-display state of the object can more appropriately be set.
According to an exemplary embodiment, the movement-and-display instructions cause movement of the object in an orientation in which a travel distance from a position of display of the object to outside of the effective display range is shortest.
According to the exemplary embodiment, since a time period for moving the object out of the effective display range and/or a time period for moving the object from the outside of the effective display range can be shortened, user's awkward feeling about movement of the object can be lessened.
According to an exemplary embodiment, a display system including a display portion capable of providing stereoscopic display and a control entity for controlling display on the display portion is provided. The display system includes an image output unit for outputting an image for left eye and an image for right eye to the display portion, a parallax calculation unit for calculating parallax produced when an object is displayed on the display portion, and a movement-and-display unit for carrying out at least one of movement of a displayed object out of an effective display range and movement of a not-displayed object into the effective display range in accordance with the calculated parallax.
According to an exemplary embodiment, a display control method performed in a computer of a display capable of providing stereoscopic display is provided. The display control method includes an image output step of outputting an image for left eye and an image for right eye to the display, a parallax calculation step of calculating parallax produced when an object is displayed on the display, and a movement-and-display step of carrying out at least one of movement of a displayed object out of an effective display range and movement of a not-displayed object into the effective display range in accordance with the calculated parallax.
A display according to an exemplary embodiment includes a display portion capable of providing stereoscopic display, an image output unit for outputting an image for left eye and an image for right eye to the display portion, a parallax calculation unit for calculating parallax produced when an object is displayed on the display portion, and a movement-and-display unit for carrying out at least one of movement of a displayed object out of an effective display range and movement of a not-displayed object into the effective display range in accordance with the calculated parallax.
The foregoing and other objects, features, aspects and advantages of the exemplary embodiment(s) will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.